1. Field of the Invention
This invention relates generally to a high temperature reactors, and, more particularly, to the reactor vessels for such reactors.
2. Description of the Problem
High temperature reactors, such as plasma reactors used for pyrolitic conversion of waste to constituent metals and organic matter, can create gaseous matter such as carbon monoxide (CO), and hydrogen that may be used in many other processes. These reactors are fed solid materials, including without limitation, municipal solid waste (MSW), which are exposed to high energy generated by a plasma arc. The energy levels are greater than the Gibbs' “Enthalpy of Formation” values for the material being processed, and, consequently, the processed material is dissociated. The result in the reactor chamber is a gas typically composed of carbon, hydrogen, nitrogen, and hydrogen chloride, acetylene, methane, polycyclics and other gases which rise to the top portion of the reactor chamber. Below that gas region is a layer of frothy “slag” in which resides oxidized metals such as silica (SiO2), Magnesium Oxide (MgO) lime (CaO) and Aluminum Oxide (Al2O3). Forming a layer on the bottom of the chamber is a bed of molten iron with certain amounts of dissolved alloys dependent on the composition of the feed materials.
The gas resulting from the conversion is useful in other industries. For example, the gas may be used to make methanol which may in turn be used to make a number of other chemicals, including butanol, MTBE and even gasoline using the Mobil process. However, unless several process variables are controlled, the purity and density of the gas is unpredictable. One variable affecting the resulting gas properties is the amount of outside air that may be drawn in to the processing system. Thus, the reaction chamber should be airtight as much as possible. Feeding the material into the reaction chamber, however, increases the likelihood of outside air being introduced and corrupting the reaction. Accordingly, it is desirable to reduce the amount of outside air that enters the reaction chamber that may be trapped within the feed material to be processed. Efforts to reduce entry of outside air into the reaction include compaction of the MSW feed materials as described in co-owned and co-pending U.S. patent Ser. No. 11/809,810, filed Jun. 1, 2007, and incorporated by reference herein.
A concern with current designs of reactor chambers is that feed of the MSW is from the top of the chamber. This results in turbulent disturbance of the slag layer, which results in increased particulate matter in the gaseous layer, which contaminates the product gases.
Additionally, it is desirable to control the velocity of the gas traveling upward in the reactor prior to extraction in order for there to be as great a likelihood as possible for reformation of the gases into useful CO and H2, for example and to decrease the likelihood of ionized gases exiting the chamber.